.dark .header {
  box-shadow: 0 0 10px #888888;
}
.dark .header .mask {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: #1A1A1A;
  z-index: 1;
}
.dark .header .left .user .name {
  color: #ffffff;
}
.dark .header .right .nav a {
  color: #ffffff;
}
.dark .header .right .nav a:hover {
  color: #2177b8;
}
